The aim of this study is to investigate communication between preschool teachers and children in documentation situations. The focus is also on what preschool teachers actually document. The research questions are: What characterizes the communication between teachers and children when these teachers are documenting at the same time? What is the focus of the documentation? To interpret this communication, Habermas' concepts of communicative and strategic action are used. Data consist of video observations, where 157?min of recordings have been analysed. The study participants are 30 children, 1-3-years old and their 7 preschool teachers. The results show that the preschool teachers either become silent observers or eager advocates of a particular discovery and that it is mainly children's achievements that are documented. What is communicated and documented by the teachers has a high degree of abstraction, and the communication is of a strategic character.